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OLEJOE
11-20-2013, 09:26 PM
Can a say bull contour barrel be recontured in to sporter barrel? Would reconturing induce stress into the barrel? Inquiring minds want to know. Anybody have any experience with this sort of thing?:confused:

J.Baker
11-20-2013, 09:46 PM
Considering ALL sporter barrels start out as bull barrels and are essentially "recontoured" to become sporter barrels, I see no reason why it would be a problem or how it would induce any stress.

All button and cut rifled barrels start out as bar stock which is cut to length, deep hole drilled, reamed to the finish bore size, then rifled. From there the process can proceed in one of two ways...

Option 1: Exterior of barrel is finished out (shank threaded, turned to final contour and crown is cut) and then the chamber is cut.

Option 2: Chamber is cut and then the exterior is finished out.

Which order is used makes no difference what-so-ever - it's just a matter of how the manufacturer has their shop setup that determines which order they go in. Savage uses Option 1.

Dennis
11-21-2013, 04:03 AM
This subject has come up several times before and there are answers both ways.

I understand reestablishing the center line of the barrel is the first step. The barrel maker "may" have proprietary steps making this process a little tough to re-establish. Barrel harmonics and concentricity of the bore are two items to mention. FYI-We do not shorten barrels more than 2" if one chooses to do so, as this process alone will affect harmonics and bore concentricity.

As Jim explained in Option 1, these processes will have to take place again after the barrel is re-contoured.

Option 2 will have to be repeated. I definitely would re-chamber the barrel especially after going to the trouble of all the above procedures. The throat I am sure will have wear, and of course before anything is done, a certified gunsmith should check the throat first, rifling, and overall condition of the barrel just to see if the barrel is a candidate to start with.

If you are paying someone to do this work for you, your better off selling your original barrel and buying a new replacement ready to go. Unless your a hobbyist, re-contouring is not cost effective. To begin with, the cost of the lathe (CNC) alone is almost to much for most shops to bear , plus you mush have someone very experienced operating it.

Even shooting competition (eg., 6.5x284), if you set back your barrel, you only gain maybe 600 to 800 extra rounds or so? This figure strictly depends on the caliber, and is only worth it if the barrel is extremely accurate. Usually your accuracy is retained after having one set back.

Just a few things to kick around, and JMO.

Considering the above, you have almost built a new barrel. You started off with a used barrel, and if your lucky, the bore and rifling are still good. The balance of the project is the same as building a new barrel.

Dennis